The present invention relates generally to bicycles, and more particularly to the mounting of front wheel quick-release hubs. Specifically, the present invention provides a self-locking safety retaining wheel mount for use with front wheel quick-release wheel mounting hubs. The mount of the present invention is particularly useful for use on front forks that were not originally designed to retain the front wheel in the event the quick-release hub was undertightened.
It is well known in the present day bicycle technology to utilize quick-release mounting devices or hubs for attaching the front wheel to each leg end piece of the bicycle front fork. Such end pieces are hereinafter referred to as a dropout, and will be understood to be either singular or plural. The use of quick-release mounts is popular in racing and touring bicycles as they facilitate convenient removal of the wheel for repair. However, concomitant with the convenience of quick-release hubs is the danger that they may be accidentally loosened, improperly installed or inadequately secured, and subsequently disengage from the bicycle, with disastrous results for both bicycle and rider. Since many of the designs for dropouts provide no means to keep the wheel attached to the forks in the event the quick-release hub is undertightened, many devices have been proposed to prevent a quick-release mounted front wheel from separating from the bicycle while riding.
U.S. Pat. No. 3,807,761 (Brilando, et al) discloses a safety clip which is mounted to the dropout on each leg of the fork by a lock washer and bolt inserted into a specially threaded aperture in the dropout. In use, the clip is positioned so as to close the opening of the front fork dropout axle slot, retaining the wheel axle in case of unintentional release of the quick-release hub. This unit requires that the dropout be modified by drilling and tapping a hole so that the mounting screw can be installed. Special tools, training and skills, typically beyond the level of the general consumer, are required for this installation. An adult of normal intelligence and ability would foreseeably have difficulty installing this safety device. Thus, the general consumer would not be expected to be able to install this device and would have to rely on the skills of a professional mechanic for such installation.
U.S. Pat. No. 4,711,459 (Liu) discloses hub retention devices which are mounted on each end of the axle quick-release hub assembly and pivots to engage a protrusion on the dropout. The protrusions disclosed by Liu typically include threaded apertures for receiving a bolt for securing fender struts and other accessories common on some, but not always found on, bicycle dropouts. The device disclosed by Liu further must be used with dropouts modified with an appropriate stud and with a wheel configured with the modified quick-release. Moreover, these latches are held securely when the quick-release hub is tightened but is free to move under inertial forces if the quick-release hub is loosened or undertightened. If the hub is loosened by the forces resulting from a collision or riding over rough terrain, the device may also move due to those same forces from the secured to an unsecured position and allow the wheel to separate from the bicycle. The skills required to properly install these safety latches exceed the level of skill of the general consumer; there is no positive preset locking position for the latches; and they can easily be installed incorrectly. In the event only one of the latches is securely tightened, the wheel still may disengage under inertial forces.
U.S. Pat. No. 4,103,922 (Brilando) discloses a pair of flexible retainer clips which mount on the end of the axle and are secured to each leg of the bicycle front fork by inserting a stud attached on the bicycle fork leg into an aperture in the clip. To release the wheel, the clip is forced off the stud, separated from the fork legs and moved aside, allowing the wheel to be removed from the fork. The bicycle front fork legs must be precisely modified or manufactured with the stud in the correct position on each leg for receiving the clip. The modification would require professional service to install. This special modification precludes use of the clip on an unmodified fork, for example when changing the wheel from one bicycle to another. This type of safety device requires mechanical skill beyond the level of skill of the general consumer and an adult of normal intelligence and ability would foreseeably have difficulty installing this safety device correctly.
U.S. Pat. No. 3,894,751 (Fuhrman, et al.) discloses retaining clips for retaining a bicycle front wheel in case of accidentally loosened wheel mounting nuts. The retaining clips are not useable with quick-release hubs however as said hubs do not provide sufficient clearance for the retaining clips to be removed, thereby not allowing the wheel to be removed from the dropouts without fully removing the quick-release hubs from the axle. This design would defeat the purpose of the quick-release unit, namely, to easily and conveniently remove the wheel. Neither Fuhrman and Zachert nor Fritz suggest means whereby their respective disclosures could be adapted to use with quick-release hubs.
The causes of inadvertent separation of the wheel from the bicycle generally form three groups: collisions, road hazards and inadequate mount design. The first refers to collisions by the rider with either stationary objects or other riders or vehicles. This is most commonly found in crowded areas, such as urban districts of cities, and in racing where many riders are crowded into limited space. In this case the handles of a quick-release hub may be caught by a portion of another bicycle, thereby releasing the hub and allowing the dislodgment of the wheel from the bicycle.
The second group is common to both racing and touring by bicycle, especially off-road touring. Hitting a hole or bump in the pathway could exert substantial force on the wheel mounting hub, thereby jarring it loose and allowing the wheel to separate from the dropout and causing the rider to fall and possibly be injured.
The final group refers to a wheel mounting apparatus that, by its design, requires some mechanical aptitude and strength or dexterity to properly operate. If the rider is a diminutive individual, such as a child, secure fastening of the wheel may not be achieved. Such an inadequately tightened or improperly fastened wheel could lead to accidental separation of the wheel from the bicycle under normal riding conditions, possibly leading to injury of the rider and product liability claims against the manufacturer since this potential misuse by the customer is foreseeable by the manufacturer.
A reliable safety device which is quick and easy to operate by any individual under all conditions such as racing or touring in all weather conditions is therefore desirable for use with quick-release hubs.